The role of fisheries sector in the coastal fishing communities of Sri Lanka

Sri Lanka is an island country with a land area of 65 610 km2. With the declaration of the exclusive economic zone (EEZ) in 1976, the country gained sovereign rights over an ocean area of 536 000 km2 and EEZ extending from 24 to 200 nm. The continental shelf is about 26 000 km2 with an average width of around 22 km, and the coastline is 1 100 km long. The total annual fish production of Sri Lanka was 25 000 t in 1952 and 269 850 t in 1998. Major fish species caught in Sri Lankan waters are skipjack, blood fish, yellow fin tuna, mullet, shark, trevally, Spanish mackerel, prawns, lobsters. Gross domestic product (GDP) is composed of services, agriculture including forestry and fishery, manufacturing, construction and mining and quarrying. Of these, the agriculture sector contributed 21% with 2.5% coming from the fisheries subsector in 1998. In 1975, fisheries contributed Rs420 million to GDP and substantially improved to Rs24 823 million (US$382 million at 1 US$ = 64.90 Sri Lanka Rupee; source: oanda.com) in 1998. Export volume from fisheries was 3 240 t in 1985, and 11 433 t in 1998; equivalent to an export value of Rs453 mil (US$7 million) to Rs6 732 mil. (US$104 million). The fisheries sector has provided direct employment opportunities to over 115 000 people and indirect benefits to 100 000 people in related occupations such as fish processing, boat building and other equipment manufacture and trade and public sector organizations. A socioeconomic survey conducted in 1996 noted a fisher population of 83 776 with 81.7% having fishing as their sole source of income, 12.5% as their main source and 4.3% as their second source. Fish is the main and preferred source of animal protein in Sri Lanka. Fish consumption accounts for 5% of the total food consumption and per capita fish consumption was 12.77 kg in 1998. However fish constitutes a substantial share of expenditure on food because of its high domestic price. The policy of almost all fisheries projects in Sri Lanka has been to maximize the fisheries resource utilization for direct extractive purposes rather than for sustainable resource management. This short-range orientation has increased the efficiency of fishing operations through the application of advanced technologies in fish capture, leading to a shift from the traditional fishing methods to the adoption of modern fishing gear. This has led to the depletion of fishery resources, particularly in the coastal waters. Thus there is a need to adopt programmes that emphasize the development of offshore fishing and thereby reduce fishing pressure in the coastal areas. Implementation of alternative livelihood opportunities would also improve the quality of life of coastal fishers.Fishery resources, Fishery surveys, Catch/effort, Trawling, Population characteristics, Biomass, Coastal fisheries, Mathematical models, Marine fisheries, Ecosystems, Socioeconomic aspects, Artisanal fishing, Economic benefits, Fishery industry, Capture fishery economics, Fish consumption, ISW, Sri Lanka,

Interaction between Coastal and Oceanic Ecosystems of the Western and Central Pacific Ocean through Predator-Prey Relationship Studies

The Western and Central Pacific Ocean sustains the highest tuna production in the world. This province is also characterized by many islands and a complex bathymetry that induces specific current circulation patterns with the potential to create a high degree of interaction between coastal and oceanic ecosystems. Based on a large dataset of oceanic predator stomach contents, our study used generalized linear models to explore the coastal-oceanic system interaction by analyzing predator-prey relationship. We show that reef organisms are a frequent prey of oceanic predators. Predator species such as albacore (Thunnus alalunga) and yellowfin tuna (Thunnus albacares) frequently consume reef prey with higher probability of consumption closer to land and in the western part of the Pacific Ocean. For surface-caught-predators consuming reef prey, this prey type represents about one third of the diet of predators smaller than 50 cm. The proportion decreases with increasing fish size. For predators caught at depth and consuming reef prey, the proportion varies with predator species but generally represents less than 10%. The annual consumption of reef prey by the yellowfin tuna population was estimated at 0.8±0.40CV million tonnes or 2.17×1012±0.40CV individuals. This represents 6.1%±0.17CV in weight of their diet. Our analyses identify some of the patterns of coastal-oceanic ecosystem interactions at a large scale and provides an estimate of annual consumption of reef prey by oceanic predators

Biology, Fishery, Conservation and Management of Indian Ocean Tuna Fisheries

The focus of the study is to explore the recent trend of the world tuna fishery with special reference to the Indian Ocean tuna fisheries and its conservation and sustainable management. In the Indian Ocean, tuna catches have increased rapidly from about 179959 t in 1980 to about 832246 t in 1995. They have continued to increase up to 2005; the catch that year was 1201465 t, forming about 26% of the world catch. Since 2006 onwards there has been a decline in the volume of catches and in 2008 the catch was only 913625 t. The Principal species caught in the Indian Ocean are skipjack and yellowfin. Western Indian Ocean contributed 78.2% and eastern Indian Ocean 21.8% of the total tuna production from the Indian Ocean. The Indian Ocean stock is currently overfished and IOTC has made some recommendations for management regulations aimed at sustaining the tuna stock. Fishing operations can cause ecological impacts of different types: by catches, damage of the habitat, mortalities caused by lost or discarded gear, pollution, generation of marine debris, etc. Periodic reassessment of the tuna potential is also required with adequate inputs from exploratory surveys as well as commercial landings and this may prevent any unsustainable trends in the development of the tuna fishing industry in the Indian Ocean

Computationally efficient implementation of video rectification in FPGA fo stereo vision applications

In order to obtain depth perception in computer vision, one needs to process pairs of stereo images. This process is computationally challenging to be carried out in real-time, because it requires the search for matches between objects in both images. Such process is significantly simplified if the images are reflected. Stereo image reflection involves a matrix transformation which when done in software will not produce real-time results. But in stereo vision applications this features is very demanding. On the other hand, applying those transformations to the video frames is very restricted by real-time constraints. Therefore, the video streaming and matrix transformation are not usually implemented in the same system. Our product is a stereo camera pair which produces a rectified real time image output with a resolution of 320x240 at a frame rate of 15FPS and delivers then via 100-Ethernet interface. We use an Spartan 3E FPGA for real-time processing within we implement an image rectification algorithm